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path: root/drivers/virtio/virtio_pci_modern.c
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2021-11-01virtio_pci: harden MSI-X interruptsJason Wang
We used to synchronize pending MSI-X irq handlers via synchronize_irq(), this may not work for the untrusted device which may keep sending interrupts after reset which may lead unexpected results. Similarly, we should not enable MSI-X interrupt until the device is ready. So this patch fixes those two issues by: 1) switching to use disable_irq() to prevent the virtio interrupt handlers to be called after the device is reset. 2) using IRQF_NO_AUTOEN and enable the MSI-X irq during .ready() This can make sure the virtio interrupt handler won't be called before virtio_device_ready() and after reset. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20211019070152.8236-5-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-05-04virtio_pci_modern: __force cast the notify mappingMichael S. Tsirkin
When switching virtio_pci_modern to use a helper for mappings we lost an __iomem tag. We should restore it. However, virtio_pci_modern is playing tricks by hiding an iomem pointer in a regular vq->priv pointer. Which is okay as long as it's all contained within a single file, but we need to __force cast the value otherwise we'll get sparse warnings. Reported-by: kernel test robot <lkp@intel.com> Fixes: 7dca6c0ea96b ("virtio-pci library: switch to use vp_modern_map_vq_notify()") Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-05-03virtio-pci library: report resource addressJason Wang
Sometimes it might be useful to report the capability physical address. One example is to report the physical address of the doorbell in order to be mapped by userspace. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210415073147.19331-7-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-05-03virtio-pci library: switch to use vp_modern_map_vq_notify()Jason Wang
This patch switch to use vp_modern_map_notify() for virtio-pci library. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210415073147.19331-3-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Reviewed-by: Eli Cohen <elic@nvidia.com>
2021-02-23virtio-pci: introduce modern device moduleJason Wang
Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-17-jasowang@redhat.com Including a bugfix: virtio: don't prompt CONFIG_VIRTIO_PCI_MODERN Cc: Arnd Bergmann <arnd@arndb.de> Cc: Anders Roxell <anders.roxell@linaro.org> Cc: Guenter Roeck <linux@roeck-us.net> Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Fixes: 86b87c9d858b6 ("virtio-pci: introduce modern device module") Signed-off-by: Jason Wang <jasowang@redhat.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Link: https://lore.kernel.org/r/20210223061905.422659-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virito-pci-modern: rename map_capability() to vp_modern_map_capability()Jason Wang
To ease the split, map_capability() was renamed to vp_modern_map_capability(). While at it, add the comments for the arguments and switch to use virtio_pci_modern_device as the first parameter. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-16-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce helper to get notification offsetJason Wang
This patch introduces help to get notification offset of modern device. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-15-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce helper for getting queue numsJason Wang
This patch introduces helper for getting queue num of modern device. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-14-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce helper for setting/geting queue sizeJason Wang
This patch introduces helper for setting/getting queue size for modern device. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-13-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce helper to set/get queue_enableJason Wang
This patch introduces a helper to set/get queue_enable for modern device. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-12-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce vp_modern_queue_address()Jason Wang
This patch introduce a helper to set virtqueue address for modern address. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-11-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce vp_modern_set_queue_vector()Jason Wang
This patch introduces a helper to set virtqueue MSI vector. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-10-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce vp_modern_generation()Jason Wang
This patch introduces vp_modern_generation() to get device generation. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-9-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce helpers for setting and getting featuresJason Wang
This patch introduces helpers for setting and getting features. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-8-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce helpers for setting and getting statusJason Wang
This patch introduces helpers to allow set and get device status. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-7-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce helper to set config vectorJason Wang
This patch introduces vp_modern_config_vector() for setting config vector. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-6-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: introduce vp_modern_remove()Jason Wang
This patch introduces vp_modern_remove() doing device resources cleanup to make it can be used. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-5-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci-modern: factor out modern device initialization logicJason Wang
This patch factors out the modern device initialization logic into a helper. Note that it still depends on the caller to enable pci device which allows the caller to use e.g devres. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-4-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci: split out modern deviceJason Wang
This patch splits out the virtio-pci modern device only attributes into another structure. While at it, a dedicated probe method for modern only attributes is introduced. This may help for split the logic into a dedicated module. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-3-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-02-23virtio-pci: do not access iomem via struct virtio_pci_device directlyJason Wang
Instead of accessing iomem via struct virito_pci_device directly, tweak to call the io accessors through the iomem structure. This will ease the splitting of modern virtio device logic. Signed-off-by: Jason Wang <jasowang@redhat.com> Link: https://lore.kernel.org/r/20210104065503.199631-2-jasowang@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2020-09-10virtio: Implement get_shm_region for PCI transportSebastien Boeuf
On PCI the shm regions are found using capability entries; find a region by searching for the capability. Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com> Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com> Signed-off-by: kbuild test robot <lkp@intel.com> Acked-by: Michael S. Tsirkin <mst@redhat.com> Cc: kvm@vger.kernel.org Cc: virtualization@lists.linux-foundation.org Cc: "Michael S. Tsirkin" <mst@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2020-08-14virtio: pci: constify ioreadX() iomem argument (as in generic implementation)Krzysztof Kozlowski
The ioreadX() helpers have inconsistent interface. On some architectures void *__iomem address argument is a pointer to const, on some not. Implementations of ioreadX() do not modify the memory under the address so they can be converted to a "const" version for const-safety and consistency among architectures. Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Cc: Allen Hubbe <allenbh@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Jiang <dave.jiang@intel.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Helge Deller <deller@gmx.de> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Jakub Kicinski <kuba@kernel.org> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Jason Wang <jasowang@redhat.com> Cc: Jon Mason <jdmason@kudzu.us> Cc: Kalle Valo <kvalo@codeaurora.org> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Paul Mackerras <paulus@samba.org> Cc: Richard Henderson <rth@twiddle.net> Cc: Rich Felker <dalias@libc.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Link: http://lkml.kernel.org/r/20200709072837.5869-5-krzk@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-05virtio_pci_modern: Fix the comment of virtio_pci_find_capability()Liao Pingfang
Fix the comment of virtio_pci_find_capability() by adding missing comment for the last parameter: bars. Fixes: 59a5b0f7bf74 ("virtio-pci: alloc only resources actually used.") Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn> Signed-off-by: Yi Wang <wang.yi59@zte.com.cn> Link: https://lore.kernel.org/r/1596455545-43556-1-git-send-email-wang.yi59@zte.com.cn Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2020-06-02virtio: add VIRTIO_RING_NO_LEGACYMatej Genci
Add macro to disable legacy vring functions. Signed-off-by: Matej Genci <matej.genci@nutanix.com> Link: https://lore.kernel.org/r/20190911124942.243713-1-matej.genci@nutanix.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2019-05-24treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 78Thomas Gleixner
Based on 1 normalized pattern(s): this work is licensed under the terms of the gnu gpl version 2 or later see the copying file in the top level directory extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 6 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190520075210.858783702@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-06-12virtio_pci: support enabling VFsTiwei Bie
There is a new feature bit allocated in virtio spec to support SR-IOV (Single Root I/O Virtualization): https://github.com/oasis-tcs/virtio-spec/issues/11 This patch enables the support for this feature bit in virtio driver. Signed-off-by: Tiwei Bie <tiwei.bie@intel.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-05-02virtio: add context flag to find vqsMichael S. Tsirkin
Allows maintaining extra context per vq. For ease of use, passing in NULL is legal and disables the feature for all vqs. Includes fixes by Christian for s390, acked by Cornelia. Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com> Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11Revert "virtio_pci: remove struct virtio_pci_vq_info"Michael S. Tsirkin
This reverts commit 5c34d002dcc7a6dd665a19d098b4f4cd5501ba1a. Conflicts: drivers/virtio/virtio_pci_common.c The cleanup seems to be one of the changes that broke hybernation for some users. We are still not sure why but revert helps. This reverts the cleanup changes but keeps the affinity support. Tested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-04-11Revert "virtio_pci: don't duplicate the msix_enable flag in struct pci_dev"Michael S. Tsirkin
This reverts commit 53a020c661741f3b87ad3ac6fa545088aaebac9b. The cleanup seems to be one of the changes that broke hybernation for some users. We are still not sure why but revert helps. Tested-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27virtio: provide a method to get the IRQ affinity mask for a virtqueueChristoph Hellwig
This basically passed up the pci_irq_get_affinity information through virtio through an optional get_vq_affinity method. It is only implemented by the PCI backend for now, and only when we use per-virtqueue IRQs. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27virtio: allow drivers to request IRQ affinity when creating VQsChristoph Hellwig
Add a struct irq_affinity pointer to the find_vqs methods, which if set is used to tell the PCI layer to create the MSI-X vectors for our I/O virtqueues with the proper affinity from the start. Compared to after the fact affinity hints this gives us an instantly working setup and allows to allocate the irq descritors node-local and avoid interconnect traffic. Last but not least this will allow blk-mq queues are created based on the interrupt affinity for storage drivers. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27virtio_pci: don't duplicate the msix_enable flag in struct pci_devChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jason Wang <jasowang@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2017-02-27virtio_pci: remove struct virtio_pci_vq_infoChristoph Hellwig
We don't really need struct virtio_pci_vq_info, as most field in there are redundant: - the vq backpointer is not strictly neede to start with - the entry in the vqs list is not needed - the generic virtqueue already has list, we only need to check if it has a callback to get the same semantics - we can use a simple array to look up the MSI-X vec if needed. - That simple array now also duoble serves to replace the per_vq_vectors flag Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-12-15virtio_pci_modern: fix complaint by sparseGonglei
drivers/virtio/virtio_pci_modern.c:66:40: warning: incorrect type in argument 2 (different base types) drivers/virtio/virtio_pci_modern.c:66:40: expected unsigned int [noderef] [usertype] <asn:2>*addr drivers/virtio/virtio_pci_modern.c:66:40: got restricted __le32 [noderef] [usertype] <asn:2>*lo drivers/virtio/virtio_pci_modern.c:67:33: warning: incorrect type in argument 2 (different base types) drivers/virtio/virtio_pci_modern.c:67:33: expected unsigned int [noderef] [usertype] <asn:2>*addr drivers/virtio/virtio_pci_modern.c:67:33: got restricted __le32 [noderef] [usertype] <asn:2>*hi drivers/virtio/virtio_pci_modern.c:150:32: warning: incorrect type in argument 2 (different base types) drivers/virtio/virtio_pci_modern.c:150:32: expected unsigned int [noderef] [usertype] <asn:2>*addr drivers/virtio/virtio_pci_modern.c:150:32: got restricted __le32 [noderef] <asn:2>*<noident> drivers/virtio/virtio_pci_modern.c:151:39: warning: incorrect type in argument 1 (different base types) drivers/virtio/virtio_pci_modern.c:151:39: expected unsigned int [noderef] [usertype] <asn:2>*addr drivers/virtio/virtio_pci_modern.c:151:39: got restricted __le32 [noderef] <asn:2>*<noident> drivers/virtio/virtio_pci_modern.c:152:32: warning: incorrect type in argument 2 (different base types) drivers/virtio/virtio_pci_modern.c:152:32: expected unsigned int [noderef] [usertype] <asn:2>*addr Signed-off-by: Gonglei <arei.gonglei@huawei.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-04-07virtio: virtio 1.0 cs04 spec compliance for resetMichael S. Tsirkin
The spec says: after writing 0 to device_status, the driver MUST wait for a read of device_status to return 0 before reinitializing the device. Cc: stable@vger.kernel.org Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Jason Wang <jasowang@redhat.com>
2016-03-02virtio_pci: Use the DMA API if enabledAndy Lutomirski
This switches to vring_create_virtqueue, simplifying the driver and adding DMA API support. This fixes virtio-pci on platforms and busses that have IOMMUs. This will break the experimental QEMU Q35 IOMMU support until QEMU is fixed. In exchange, it fixes physical virtio hardware as well as virtio-pci running under Xen. Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-03-02virtio-pci: read the right virtio_pci_notify_cap fieldLadi Prosek
Looks like a copy-paste bug. The value is used as an optimization and a wrong value probably isn't causing any serious damage. Found when porting this code to Windows. Signed-off-by: Ladi Prosek <lprosek@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2016-01-12virtio: make find_vqs() checkpatch.pl-friendlyStefan Hajnoczi
checkpatch.pl wants arrays of strings declared as follows: static const char * const names[] = { "vq-1", "vq-2", "vq-3" }; Currently the find_vqs() function takes a const char *names[] argument so passing checkpatch.pl's const char * const names[] results in a compiler error due to losing the second const. This patch adjusts the find_vqs() prototype and updates all virtio transports. This makes it possible for virtio_balloon.c, virtio_input.c, virtgpu_kms.c, and virtio_rpmsg_bus.c to use the checkpatch.pl-friendly type. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Acked-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
2015-06-24virtio-pci: alloc only resources actually used.Gerd Hoffmann
Move resource allocation from common code to legacy and modern code. Only request resources actually used, i.e. bar0 in legacy mode and the bar(s) specified by capabilities in modern mode. Signed-off-by: Gerd Hoffmann <kraxel@redhat.com> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-04-15virtio_pci: support non-legacy balloon devicesMichael S. Tsirkin
virtio_device_is_legacy_only is always false now, drop the test from virtio pci. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-01virtio_pci_modern: switch to type-safe io accessorsMichael S. Tsirkin
As Rusty noted, we were accessing queue_enable with an incorrect width. Switch to type-safe accessors so we don't make this mistake again in the future. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-04-01virtio_pci_modern: type-safe io accessorsMichael S. Tsirkin
The spec is very clear on this: 4.1.3.1 Driver Requirements: PCI Device Layout The driver MUST access each field using the “natural” access method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for 16-bit fields and 8-bit accesses for 8-bit fields. Add type-safe wrappers to prevent access with incorrect width. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-02-11virtio_pci: use 16-bit accessor for queue_enable.Rusty Russell
Since PCI is little endian, 8-bit access might work, but the spec section is very clear on this: 4.1.3.1 Driver Requirements: PCI Device Layout The driver MUST access each field using the “natural” access method, i.e. 32-bit accesses for 32-bit fields, 16-bit accesses for 16-bit fields and 8-bit accesses for 8-bit fields. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Acked-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21virtio_pci_modern: drop an unused functionMichael S. Tsirkin
release function in modern driver is unused: it's a left-over from when each driver had to have its own release. Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21virtio_pci_modern: support devices with no configMichael S. Tsirkin
Virtio 1.0 spec lists device config as optional. Set get/set callbacks to NULL. Drivers can check that and fail gracefully. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21virtio_pci_modern: reduce number of mappingsMichael S. Tsirkin
We don't know the # of VQs that drivers are going to use so it's hard to predict how much memory we'll need to map. However, the relevant capability does give us an upper limit. If that's below a page, we can reduce the number of required mappings by mapping it all once ahead of the time. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-01-21virtio_pci: macros for PCI layout offsetsRusty Russell
QEMU wants it, so why not? Trust, but verify. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2015-01-21virtio_pci: modern driverMichael S. Tsirkin
Lightly tested against qemu. One thing *not* implemented here is separate mappings for descriptor/avail/used rings. That's nice to have, will be done later after we have core support. This also exposes the PCI layout to userspace, and adds macros for PCI layout offsets: QEMU wants it, so why not? Trust, but verify. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>